Assessment of potential habitat for <I>Ursus thibetanus</I> in the Qinling Moun-tains

Abstract

Understanding the distribution of suitable habitat of target species and their relationship with en- vironment are critical to formulating effective protective measures. The Qinling Mountains contain important habitat for Ursus thibetanus. A predictive habitat distribution map of this species was estimated using the Maximum Entropy (MAXENT) model with a total of 68 recorded points of known bear occurrence and 34 environmental factors. The distribution of potential habitat and its relationship with major environmental factors were analyzed and a gap analysis was carried out in light of existing nature reserves. Habitat corridor networks were also planned using resistance surface and least-cost analysis. Results showed that human in- terference and landuse type were the main factors influencing habitat choice of U. thibetanus. Three variables including residential density, distance to grassland and distance to cultivated land had the greatest effect on habitat selection, with a contribution of 21.4%, 17.5% and 15.9% respectively, followed by the distance to broad-leaf forest and distance to water. Estimated suitable habitat for U. thibetanus was distributed mainly in the middle and western portions of the Qinling Mountains and occupied 19.23% of the Mountains' total area. Gap analysis showed that approximately 23.49% of the bear's predicted suitable habitat was protected within the nature reserves, but that 8,480 km 2 of suitable habitat was outside these reserves. In order to protect U. thibetanus and its habitat more effectively, suggestions for the construction of 12 habitat corridors and a sys- tematic conservation planning process integrating other species' needs were proposed.